MBF Knowledge Base

Winsock error 10053 seems to be occuring on SMTP mail to and from MDaemon. How do I prevent this?

Winsock error 10053 usually occurs with routers, firewalls and proxies. Are you using any of these? If you're using a router, please be sure that the MTU setting is at 1500. Then, see if this resolves your issue. If not, double check the MTU setting on the MDaemon server (the MTU setting is in the registry).

If you are using a firewall, please click here to see which ports you need to have open in order for MDaemon to run properly.

If you are using a proxy server, make sure that the port settings you are using do not conflict with any that may be set in the proxy server itself. For example, SMTP email normally takes place on port 25. Since an IP address can only have a single port 25, two servers cannot both listen for SMTP email at the same time on the same machine.

If you find it necessary to channel mail through a proxy, MDaemon allows you to configure the ports which it will use to send and receive SMTP/POP/IMAP transactions. You may need to set these ports to non-standard values in order to filter your SMTP/POP/IMAP transactions through the proxy server.